Blue Bottle Flies are
from the Blow Fly family. They are larger than house flies,
growing about half an inch long. Their head
and thorax
(front and middle sections) are gray, the abdomen
(large rear section) is bright metallic blue. They have red
eyes and clear wings.

Blue Bottle Flies live
just about anywhere, including woods, fields, parks, and
farms. They seem to prefer shady places. Blue Bottle Flies
often enter homes.

This fly eats from dead
animals or meat, living animals with open wounds, animal
poop, or some other decaying
matter.

After mating, the female
Blue Bottle Flies lays her eggs in the same place she feeds,
usually in a dead animal. The eggs quickly hatch, and the
young larvae, called maggots,
eat immediately. The maggots are whitish with small black
hooks to tear flesh with. Their saliva
helps dissolve (melt) the flesh so they can eat it more
easily.

After a week or so of
feeding, the larvae crawl away to a dry place and burrow a
little ways into soil. They then become pupae
(resting stage). Pupae are tough brown coccoons.

After two or three weeks,
adult Blue Bottle Flies come out of the pupae.

Blue Bottle Flies
breed
often during the warm months. Both larvae and pupae can live
through the winter, but adults die when it gets too
cold.

Blue Bottle Flies
sometimes lay eggs in the wound of a living animal. The
larvae, when they hatch, eat from the host
animal. This is called "myiasis" and can cause infections in
the animal.

Because these flies are
attracted to foul-smelling things, like dead animals and
poop, they sometimes fly to plants with bad-smelling flowers
(like Greenbrier) or fungi (like Elegant Stinkhorn). Blue
Bottle Flies end up helping these organisms because they
transport pollen
or spores
so that they can grow new plants or mushrooms.

Blue Bottle Flies can be annoying
when they fly into homes and land on meat intended as food. But most
of the time they are a great help to people. By eating dead animals,
poop, and other unpleasant things, they get rid of them for us.
Without bottle flies and other creatures decomposing
these items, they would just sit there grossing us out. Once Blue
Bottle Flies' larvae begin eating, a dead animal stops smelling
almost immediately.

Another way Blue Bottle Flies help
us is when scientists study them on a dead person's body. This may
sound unpleasant, but the presence of bottle fly larvae can tell us
how long the person has been dead, and this information is used as
evidence when crimes have been committed.